AFM Analysis of Gallid Herpesvirus 1 Casey Ross Mullikin REU Faculty Mentor: Dr. Steve Tung REU Graduate Mentor: Brock Schulte
Objective Utilize Atomic Force Microscopy to measure electrical properties of Gallid Herpesvirus 1 (Chicken Herpes) Use Viral electrical properties as a detection scheme and identification tool
AFM Schematic http://upload.wikimedia.org/wikipedia/commons/7/7c/Atomic_force_microscope_block_diagram.svg
Equipment Scanner Agilent 5500 AFM Nose Cone
Cantilever Tip Type Used Dimensions Materials Contact Surf 0.2 N/m 13 kHz Dimensions Length: 450 μm Width: 50 μm Thickness: 2 μm Materials Si Cr/Pt
Herpesvirus Diagram http://www.biografix.de/biografix/english/images/2/p_2b2a.jpg
Virus Known as Properties Gallid Herpesvirus 1 Avian Herpesvirus 1 Infectious Laryngotracheitis Chicken Herpes Properties Spherical 200-400 nm RNA Virus 5 Glycoprotein Subtypes
Scans Beads Virus
Impedance Impedance Analyzer Like resistance Measurement of opposition to a sinusoidal current Imaginary number in the form: Z=R+jX Reactance is a dielectric property of the substance If X>0 it is considered to be Inductive If X<0 it is considered to be Capacitive Absolute Impedance (Z) and Phase Angle (θ) were Measured Impedance Analyzer
Impedance Values Frequency (Hz) ITO (Ω) Bead (Ω) Virus (Ω) Buffer (Ω) %Difference 100000 55780.83 64235.83 67880.56 63833.33 5.37 150000 37740.83 42807.50 44905.56 42436.67 4.67 200000 28532.50 32364.17 33467.78 32898.89 3.30 250000 22622.50 26210.00 26744.44 25721.11 2.00 300000 18939.17 21940.00 20172.22 18837.78 8.76 350000 16356.67 18953.33 16358.89 15126.11 15.86 400000 14292.50 16544.17 13036.22 11956.83 26.91 450000 12696.67 14786.67 12822.22 12365.06 15.32 500000 11904.17 13920.83 14034.22 14154.00 0.81 550000 11330.00 13340.83 13799.78 13801.00 3.33 600000 11124.17 13069.17 13221.44 12896.78 1.15 650000 11177.67 13037.50 12581.89 11702.33 3.62 7.59
Conclusions The overall Dielectric Constant of the virus was determined to be approximately 2.4 This value should be unique to this virus and thus allow for its identification via an infected sample analysis.
References *1 Research Solutions & Resources LLC. http://www.consultrsr.com/resources/eis/cpe1.htm *2 Comparison of Electrical Properties of Viruses Studied by AC Capacitance Scanning Probe Microscopy. Robert I. MacCuspie, Nurxat Nuraje, Sang-Yup Lee, Anne Runge, and Hiroshi Matsui *3 ZView Download. http://www.scribner.com/index.php?option=com_content&task=view&id=36&Itemid=41 *4 Human Herpes Virus 3. www.ncbi.nlm.nih.gov/.../00.031.1.01.001.htm & http://web.uct.ac.za/depts/mmi/stannard/herpes.html
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